1. Field of the Invention
The present invention relates to an improved linear movement ball guideway, and more particularly to a linear movement ball guideway which includes a slide block, a guide rail and multiple loaded and unloaded ball members, wherein the guide rail is formed with two lateral concave surface, while the slide block is formed with corresponding convex surface and the concave surface and convex surface are formed with Gothic type ball member grooves defining lateral ball member passages. An upper portion of the slide block are formed semicircular surface defining upper ball member passages, whereby a top point of the loaded ball member contacts with the semicircular surface, while a bottom point of the loaded ball member contacts with an upper surface of the guide rail, whereby the turning movement of the ball members is smoothened and the load-bearing ability thereof is increased. Also, the manufacturing of the guide rail and slide block is facilitated. (FIG. 1)
2. Description of the Prior Art
A conventional linear movement guideway is shown in FIG. 2. The guide rail 1 and slide block 2 thereof are respectively formed with two pairs of lateral Goethe type grooves 3 and 4, whereby multiple loaded ball members 5 are disposed therein to bear the load on the slide block 2. The slide block 2 includes two end caps formed with turning grooves 8 so that the ball members 5 can circularly roll within the Gothic type grooves with the slide block 2 continuously linearly sliding forward along the guide rail 1. In such design, the load in all directions will be born by the lateral Gothic type contacting ball members 5 so that when the ball members 5 bear the upper load, a slide deflection will take place. During manufacturing, if the contacting profile of the lateral ball members is poor, the slide deflection will be greater and the bearing ability of the ball members will be greatly reduced and the installation accuracy will be difficult to be controlled. Moreover, the ball member turning passages 8 of the end caps 6 are limited by the width of the slide block main body 7 so that the ball members can hardly turn through large distance and the smoothness of the turning movement of the ball members will be reduced.